1/* SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note */
2#ifndef _UAPI_LINUX_FANOTIFY_H
3#define _UAPI_LINUX_FANOTIFY_H
4
5#include <linux/types.h>
6
7/* the following events that user-space can register for */
8#define FAN_ACCESS 0x00000001 /* File was accessed */
9#define FAN_MODIFY 0x00000002 /* File was modified */
10#define FAN_ATTRIB 0x00000004 /* Metadata changed */
11#define FAN_CLOSE_WRITE 0x00000008 /* Writtable file closed */
12#define FAN_CLOSE_NOWRITE 0x00000010 /* Unwrittable file closed */
13#define FAN_OPEN 0x00000020 /* File was opened */
14#define FAN_MOVED_FROM 0x00000040 /* File was moved from X */
15#define FAN_MOVED_TO 0x00000080 /* File was moved to Y */
16#define FAN_CREATE 0x00000100 /* Subfile was created */
17#define FAN_DELETE 0x00000200 /* Subfile was deleted */
18#define FAN_DELETE_SELF 0x00000400 /* Self was deleted */
19#define FAN_MOVE_SELF 0x00000800 /* Self was moved */
20#define FAN_OPEN_EXEC 0x00001000 /* File was opened for exec */
21
22#define FAN_Q_OVERFLOW 0x00004000 /* Event queued overflowed */
23#define FAN_FS_ERROR 0x00008000 /* Filesystem error */
24
25#define FAN_OPEN_PERM 0x00010000 /* File open in perm check */
26#define FAN_ACCESS_PERM 0x00020000 /* File accessed in perm check */
27#define FAN_OPEN_EXEC_PERM 0x00040000 /* File open/exec in perm check */
28
29#define FAN_EVENT_ON_CHILD 0x08000000 /* Interested in child events */
30
31#define FAN_RENAME 0x10000000 /* File was renamed */
32
33#define FAN_ONDIR 0x40000000 /* Event occurred against dir */
34
35/* helper events */
36#define FAN_CLOSE (FAN_CLOSE_WRITE | FAN_CLOSE_NOWRITE) /* close */
37#define FAN_MOVE (FAN_MOVED_FROM | FAN_MOVED_TO) /* moves */
38
39/* flags used for fanotify_init() */
40#define FAN_CLOEXEC 0x00000001
41#define FAN_NONBLOCK 0x00000002
42
43/* These are NOT bitwise flags. Both bits are used together. */
44#define FAN_CLASS_NOTIF 0x00000000
45#define FAN_CLASS_CONTENT 0x00000004
46#define FAN_CLASS_PRE_CONTENT 0x00000008
47
48/* Deprecated - do not use this in programs and do not add new flags here! */
49#define FAN_ALL_CLASS_BITS (FAN_CLASS_NOTIF | FAN_CLASS_CONTENT | \
50 FAN_CLASS_PRE_CONTENT)
51
52#define FAN_UNLIMITED_QUEUE 0x00000010
53#define FAN_UNLIMITED_MARKS 0x00000020
54#define FAN_ENABLE_AUDIT 0x00000040
55
56/* Flags to determine fanotify event format */
57#define FAN_REPORT_PIDFD 0x00000080 /* Report pidfd for event->pid */
58#define FAN_REPORT_TID 0x00000100 /* event->pid is thread id */
59#define FAN_REPORT_FID 0x00000200 /* Report unique file id */
60#define FAN_REPORT_DIR_FID 0x00000400 /* Report unique directory id */
61#define FAN_REPORT_NAME 0x00000800 /* Report events with name */
62#define FAN_REPORT_TARGET_FID 0x00001000 /* Report dirent target id */
63
64/* Convenience macro - FAN_REPORT_NAME requires FAN_REPORT_DIR_FID */
65#define FAN_REPORT_DFID_NAME (FAN_REPORT_DIR_FID | FAN_REPORT_NAME)
66/* Convenience macro - FAN_REPORT_TARGET_FID requires all other FID flags */
67#define FAN_REPORT_DFID_NAME_TARGET (FAN_REPORT_DFID_NAME | \
68 FAN_REPORT_FID | FAN_REPORT_TARGET_FID)
69
70/* Deprecated - do not use this in programs and do not add new flags here! */
71#define FAN_ALL_INIT_FLAGS (FAN_CLOEXEC | FAN_NONBLOCK | \
72 FAN_ALL_CLASS_BITS | FAN_UNLIMITED_QUEUE |\
73 FAN_UNLIMITED_MARKS)
74
75/* flags used for fanotify_modify_mark() */
76#define FAN_MARK_ADD 0x00000001
77#define FAN_MARK_REMOVE 0x00000002
78#define FAN_MARK_DONT_FOLLOW 0x00000004
79#define FAN_MARK_ONLYDIR 0x00000008
80/* FAN_MARK_MOUNT is 0x00000010 */
81#define FAN_MARK_IGNORED_MASK 0x00000020
82#define FAN_MARK_IGNORED_SURV_MODIFY 0x00000040
83#define FAN_MARK_FLUSH 0x00000080
84/* FAN_MARK_FILESYSTEM is 0x00000100 */
85#define FAN_MARK_EVICTABLE 0x00000200
86/* This bit is mutually exclusive with FAN_MARK_IGNORED_MASK bit */
87#define FAN_MARK_IGNORE 0x00000400
88
89/* These are NOT bitwise flags. Both bits can be used togther. */
90#define FAN_MARK_INODE 0x00000000
91#define FAN_MARK_MOUNT 0x00000010
92#define FAN_MARK_FILESYSTEM 0x00000100
93
94/*
95 * Convenience macro - FAN_MARK_IGNORE requires FAN_MARK_IGNORED_SURV_MODIFY
96 * for non-inode mark types.
97 */
98#define FAN_MARK_IGNORE_SURV (FAN_MARK_IGNORE | FAN_MARK_IGNORED_SURV_MODIFY)
99
100/* Deprecated - do not use this in programs and do not add new flags here! */
101#define FAN_ALL_MARK_FLAGS (FAN_MARK_ADD |\
102 FAN_MARK_REMOVE |\
103 FAN_MARK_DONT_FOLLOW |\
104 FAN_MARK_ONLYDIR |\
105 FAN_MARK_MOUNT |\
106 FAN_MARK_IGNORED_MASK |\
107 FAN_MARK_IGNORED_SURV_MODIFY |\
108 FAN_MARK_FLUSH)
109
110/* Deprecated - do not use this in programs and do not add new flags here! */
111#define FAN_ALL_EVENTS (FAN_ACCESS |\
112 FAN_MODIFY |\
113 FAN_CLOSE |\
114 FAN_OPEN)
115
116/*
117 * All events which require a permission response from userspace
118 */
119/* Deprecated - do not use this in programs and do not add new flags here! */
120#define FAN_ALL_PERM_EVENTS (FAN_OPEN_PERM |\
121 FAN_ACCESS_PERM)
122
123/* Deprecated - do not use this in programs and do not add new flags here! */
124#define FAN_ALL_OUTGOING_EVENTS (FAN_ALL_EVENTS |\
125 FAN_ALL_PERM_EVENTS |\
126 FAN_Q_OVERFLOW)
127
128#define FANOTIFY_METADATA_VERSION 3
129
130struct fanotify_event_metadata {
131 __u32 event_len;
132 __u8 vers;
133 __u8 reserved;
134 __u16 metadata_len;
135 __aligned_u64 mask;
136 __s32 fd;
137 __s32 pid;
138};
139
140#define FAN_EVENT_INFO_TYPE_FID 1
141#define FAN_EVENT_INFO_TYPE_DFID_NAME 2
142#define FAN_EVENT_INFO_TYPE_DFID 3
143#define FAN_EVENT_INFO_TYPE_PIDFD 4
144#define FAN_EVENT_INFO_TYPE_ERROR 5
145
146/* Special info types for FAN_RENAME */
147#define FAN_EVENT_INFO_TYPE_OLD_DFID_NAME 10
148/* Reserved for FAN_EVENT_INFO_TYPE_OLD_DFID 11 */
149#define FAN_EVENT_INFO_TYPE_NEW_DFID_NAME 12
150/* Reserved for FAN_EVENT_INFO_TYPE_NEW_DFID 13 */
151
152/* Variable length info record following event metadata */
153struct fanotify_event_info_header {
154 __u8 info_type;
155 __u8 pad;
156 __u16 len;
157};
158
159/*
160 * Unique file identifier info record.
161 * This structure is used for records of types FAN_EVENT_INFO_TYPE_FID,
162 * FAN_EVENT_INFO_TYPE_DFID and FAN_EVENT_INFO_TYPE_DFID_NAME.
163 * For FAN_EVENT_INFO_TYPE_DFID_NAME there is additionally a null terminated
164 * name immediately after the file handle.
165 */
166struct fanotify_event_info_fid {
167 struct fanotify_event_info_header hdr;
168 __kernel_fsid_t fsid;
169 /*
170 * Following is an opaque struct file_handle that can be passed as
171 * an argument to open_by_handle_at(2).
172 */
173 unsigned char handle[];
174};
175
176/*
177 * This structure is used for info records of type FAN_EVENT_INFO_TYPE_PIDFD.
178 * It holds a pidfd for the pid that was responsible for generating an event.
179 */
180struct fanotify_event_info_pidfd {
181 struct fanotify_event_info_header hdr;
182 __s32 pidfd;
183};
184
185struct fanotify_event_info_error {
186 struct fanotify_event_info_header hdr;
187 __s32 error;
188 __u32 error_count;
189};
190
191/*
192 * User space may need to record additional information about its decision.
193 * The extra information type records what kind of information is included.
194 * The default is none. We also define an extra information buffer whose
195 * size is determined by the extra information type.
196 *
197 * If the information type is Audit Rule, then the information following
198 * is the rule number that triggered the user space decision that
199 * requires auditing.
200 */
201
202#define FAN_RESPONSE_INFO_NONE 0
203#define FAN_RESPONSE_INFO_AUDIT_RULE 1
204
205struct fanotify_response {
206 __s32 fd;
207 __u32 response;
208};
209
210struct fanotify_response_info_header {
211 __u8 type;
212 __u8 pad;
213 __u16 len;
214};
215
216struct fanotify_response_info_audit_rule {
217 struct fanotify_response_info_header hdr;
218 __u32 rule_number;
219 __u32 subj_trust;
220 __u32 obj_trust;
221};
222
223/* Legit userspace responses to a _PERM event */
224#define FAN_ALLOW 0x01
225#define FAN_DENY 0x02
226#define FAN_AUDIT 0x10 /* Bitmask to create audit record for result */
227#define FAN_INFO 0x20 /* Bitmask to indicate additional information */
228
229/* No fd set in event */
230#define FAN_NOFD -1
231#define FAN_NOPIDFD FAN_NOFD
232#define FAN_EPIDFD -2
233
234/* Helper functions to deal with fanotify_event_metadata buffers */
235#define FAN_EVENT_METADATA_LEN (sizeof(struct fanotify_event_metadata))
236
237#define FAN_EVENT_NEXT(meta, len) ((len) -= (meta)->event_len, \
238 (struct fanotify_event_metadata*)(((char *)(meta)) + \
239 (meta)->event_len))
240
241#define FAN_EVENT_OK(meta, len) ((long)(len) >= (long)FAN_EVENT_METADATA_LEN && \
242 (long)(meta)->event_len >= (long)FAN_EVENT_METADATA_LEN && \
243 (long)(meta)->event_len <= (long)(len))
244
245#endif /* _UAPI_LINUX_FANOTIFY_H */
246

source code of linux/include/uapi/linux/fanotify.h